Earth’s surface will almost certainly not warm up four or five degrees Celsius by 2100, according to a study released Wednesday which, if correct, voids worst-case UN climate change predictions. A revised calculation of how greenhouse gases drive up the planet’s temperature reduces the range of possible end-of-century outcomes by more than half, researchers said in the report, published in the journal Nature. How effectively the world slashes CO2 and methane emissions, improves energy efficiency, and develops technologies to remove CO2 from the air will determine whether climate change remains manageable or unleashes a maelstrom of human misery.

Scientists believe they may have discovered the cause of an epidemic that struck Mexico’s Aztec population in 1545, killing up to 15 million people. In a paper published in Nature Ecology & Evolution, they describe how DNA extracted from the teeth of 29 skeletons buried in a cemetery in southern Mexico revealed previously unidentified traces of the salmonella enterica bacterium. The epidemic was one of several to hit the indigenous population soon after the arrival of Europeans in the early 16th century.

Women are being left at risk of repeat heart attacks and early death because doctors see heart disease as a male problem, a new study has shown. Researchers from The University of Leeds and the British Heart Foundation claim women are dying because many are not offered stents to unblock arteries, or prescribed statins, after their first heart attack. Around 42,000 men and 28,000 women die from coronary heart disease in Britain each year, with most deaths related to an original heart attack. But the new study, which looked at data from more than 180,000 people over 10 years, found three times the expected number of women died in the first year of a heart attack, compared to men. A large percentage of women were not prescribed statins Credit: Kumar Sriskandan / Alamy Experts claim women are being denied life saving treatment because they are not considered at high risk. “We need to work harder to shift the perception that heart attacks only affect a certain type of person,” said Professor Chris Gale, Professor of Cardiovascular Medicine and Honorary Consultant Cardiologist at the University of Leeds who co-authored the study. “Typically, when we think of a heart attack patient, we see a middle-aged man who is overweight, has diabetes and smokes. This is not always the case. Heart attacks affect the wider spectrum of the population – including women. “The findings from this study suggest that there are clear and simple ways to improve the outcomes of women who have a heart attack ­­– we must ensure equal provision of evidence-based treatments for women.” Heart attack: Symptoms and treatment The research found that women were less likely than men to receive the recommended treatments after a heart attack. Women who had a the type of attack where the coronary artery is completely blocked by a blood clot, were 34 per cent less likely than men to receive procedures which clear blocked arteries and restore blood flow to the heart, such as bypass surgery or a stent. They were also 24 per cent less likely to be prescribed statins, which help to prevent a second heart attack, and 16 per cent less likely to recommended aspirin, which helps to prevent blood clots. Critically, when women did receive all of the treatments recommended for patients who have suffered a heart attack, the number of women dying decreased dramatically. Previous BHF research has also shown that women are 50 per cent more likely than men to receive the wrong initial diagnosis and are less likely to get a pre-hospital ECG, which is essential for swift diagnosis and treatment. Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, said: “Heart attacks are often seen as a male health issue, but more women die from coronary heart disease than breast cancer in the UK. “The findings from this research are concerning – women are dying because they are not receiving proven treatments to save lives after a heart attack. “We urgently need to raise awareness of this issue as it’s something that can be easily changed. By simply ensuring more women receive the recommended treatments, we’ll be able to help more families avoid the heartbreak of losing a loved one to heart disease.” Women were less likely than men to receive artery opening surgery or a heart bypass Researchers worked with the Karolinksa Institutet in Sweden, and the findings are based on Swedish health records between 2003 and 2013. But Sweden has one of the best healthcare systems in the world, so the experts believe the situation could be even worse in Britain. “Sweden is a leader in healthcare, with one of the lowest mortality rates from heart attacks, yet we still see this disparity in treatment and outcomes between men and women,” added Prof Gale. “In all likelihood, the situation for women in the UK may be worse.” The research was published in the Journal of the American Heart Association.

By Timothy Gardner WASHINGTON (Reuters) – Melting Arctic sea ice could render sun-soaked California vulnerable to a recurrence of the severe drought suffered in recent years as it is likely to cause high pressure systems that push away rain-bearing storms, a study released on Tuesday said. As temperatures rise, the Arctic Ocean is expected to become ice-free within two or three decades, resulting in more of the sun’s heat being stored in the Arctic Ocean, leading to atmospheric circulation changes and cloud formations in the tropical Pacific that move north. “This has the potential to make a drought very similar to the one we had in 2012 to 2016,” said Ivana Cvijanovic, an atmospheric scientist at the Department of Energy’s Lawrence Livermore National Laboratory.

By Dan Whitcomb LOS ANGELES (Reuters) – Firearms-related deaths and injuries increased 70 percent in parts of California in the weeks after gun shows in neighboring Nevada, which has fewer regulations on such events, a University of California, Berkeley study released on Monday found. The research could help prevent gun deaths by charting a pattern between where weapons are purchased at gun shows and where shootings take place, according to the authors. The study, which was partly funded by the National Institutes of Health, examined firearm injury rates before and after California and Nevada gun shows between 2005 and 2013 in areas of California near the shows.

As many as three million people in the United States carry a loaded handgun daily, while nine million do so at least once a month, according to a US study Thursday. Most of these gun-toting Americans are young men, live in the south and say personal protection is a top reason for walking around with a deadly weapon, said the report in the American Journal of Public Health. “It was important to study handgun carrying because about 90 percent of all firearm homicides and nonfatal firearm crimes for which the type of firearm is known are committed with a handgun,” said lead author Ali Rowhani-Rahbar, an associate professor of epidemiology at the University of Washington School of Public Health.